// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef NET_HTTP_HTTP_SERVER_PROPERTIES_IMPL_H_
#define NET_HTTP_HTTP_SERVER_PROPERTIES_IMPL_H_

#include <stddef.h>
#include <stdint.h>

#include <deque>
#include <map>
#include <set>
#include <string>
#include <vector>

#include "base/macros.h"
#include "base/memory/weak_ptr.h"
#include "base/threading/non_thread_safe.h"
#include "base/values.h"
#include "net/base/host_port_pair.h"
#include "net/base/ip_address.h"
#include "net/base/linked_hash_map.h"
#include "net/base/net_export.h"
#include "net/http/http_server_properties.h"

namespace base {
class ListValue;
}

namespace net {

struct AlternativeServiceHash {
    size_t operator()(const net::AlternativeService& entry) const
    {
        return entry.protocol ^ std::hash<std::string>()(entry.host) ^ entry.port;
    }
};

// The implementation for setting/retrieving the HTTP server properties.
class NET_EXPORT HttpServerPropertiesImpl
    : public HttpServerProperties,
      NON_EXPORTED_BASE(public base::NonThreadSafe) {
public:
    HttpServerPropertiesImpl();
    ~HttpServerPropertiesImpl() override;

    // Initializes |spdy_servers_map_| with the servers (host/port) from
    // |spdy_servers| that either support SPDY or not.
    void InitializeSpdyServers(std::vector<std::string>* spdy_servers,
        bool support_spdy);

    void InitializeAlternativeServiceServers(
        AlternativeServiceMap* alternate_protocol_servers);

    void InitializeSpdySettingsServers(SpdySettingsMap* spdy_settings_map);

    void InitializeSupportsQuic(IPAddress* last_address);

    void InitializeServerNetworkStats(
        ServerNetworkStatsMap* server_network_stats_map);

    void InitializeQuicServerInfoMap(QuicServerInfoMap* quic_server_info_map);

    // Get the list of servers (host/port) that support SPDY. The max_size is the
    // number of MRU servers that support SPDY that are to be returned.
    void GetSpdyServerList(base::ListValue* spdy_server_list,
        size_t max_size) const;

    // Returns flattened string representation of the |host_port_pair|. Used by
    // unittests.
    static std::string GetFlattenedSpdyServer(const HostPortPair& host_port_pair);

    // Returns the canonical host suffix for |host|, or nullptr if none
    // exists.
    const std::string* GetCanonicalSuffix(const std::string& host) const;

    // -----------------------------
    // HttpServerProperties methods:
    // -----------------------------

    void Clear() override;
    bool SupportsRequestPriority(const url::SchemeHostPort& server) override;
    bool GetSupportsSpdy(const url::SchemeHostPort& server) override;
    void SetSupportsSpdy(const url::SchemeHostPort& server,
        bool support_spdy) override;
    bool RequiresHTTP11(const HostPortPair& server) override;
    void SetHTTP11Required(const HostPortPair& server) override;
    void MaybeForceHTTP11(const HostPortPair& server,
        SSLConfig* ssl_config) override;
    AlternativeServiceVector GetAlternativeServices(
        const url::SchemeHostPort& origin) override;
    bool SetAlternativeService(const url::SchemeHostPort& origin,
        const AlternativeService& alternative_service,
        base::Time expiration) override;
    bool SetAlternativeServices(const url::SchemeHostPort& origin,
        const AlternativeServiceInfoVector&
            alternative_service_info_vector) override;
    void MarkAlternativeServiceBroken(
        const AlternativeService& alternative_service) override;
    void MarkAlternativeServiceRecentlyBroken(
        const AlternativeService& alternative_service) override;
    bool IsAlternativeServiceBroken(
        const AlternativeService& alternative_service) const override;
    bool WasAlternativeServiceRecentlyBroken(
        const AlternativeService& alternative_service) override;
    void ConfirmAlternativeService(
        const AlternativeService& alternative_service) override;
    const AlternativeServiceMap& alternative_service_map() const override;
    std::unique_ptr<base::Value> GetAlternativeServiceInfoAsValue()
        const override;
    const SettingsMap& GetSpdySettings(
        const url::SchemeHostPort& server) override;
    bool SetSpdySetting(const url::SchemeHostPort& server,
        SpdySettingsIds id,
        SpdySettingsFlags flags,
        uint32_t value) override;
    void ClearSpdySettings(const url::SchemeHostPort& server) override;
    void ClearAllSpdySettings() override;
    const SpdySettingsMap& spdy_settings_map() const override;
    bool GetSupportsQuic(IPAddress* last_address) const override;
    void SetSupportsQuic(bool used_quic, const IPAddress& address) override;
    void SetServerNetworkStats(const url::SchemeHostPort& server,
        ServerNetworkStats stats) override;
    const ServerNetworkStats* GetServerNetworkStats(
        const url::SchemeHostPort& server) override;
    const ServerNetworkStatsMap& server_network_stats_map() const override;
    bool SetQuicServerInfo(const QuicServerId& server_id,
        const std::string& server_info) override;
    const std::string* GetQuicServerInfo(const QuicServerId& server_id) override;
    const QuicServerInfoMap& quic_server_info_map() const override;
    size_t max_server_configs_stored_in_properties() const override;
    void SetMaxServerConfigsStoredInProperties(
        size_t max_server_configs_stored_in_properties) override;

private:
    friend class HttpServerPropertiesImplPeer;

    // |spdy_servers_map_| has flattened representation of servers
    // (scheme, host, port) that either support or not support SPDY protocol.
    typedef base::MRUCache<std::string, bool> SpdyServersMap;
    typedef std::map<url::SchemeHostPort, url::SchemeHostPort> CanonicalHostMap;
    typedef std::vector<std::string> CanonicalSufficList;
    typedef std::set<HostPortPair> Http11ServerHostPortSet;

    // Linked hash map from AlternativeService to expiration time.  This container
    // is a queue with O(1) enqueue and dequeue, and a hash_map with O(1) lookup
    // at the same time.
    typedef linked_hash_map<AlternativeService,
        base::TimeTicks,
        AlternativeServiceHash>
        BrokenAlternativeServices;
    // Map to the number of times each alternative service has been marked broken.
    typedef std::map<AlternativeService, int> RecentlyBrokenAlternativeServices;

    // Return the iterator for |server|, or for its canonical host, or end.
    AlternativeServiceMap::const_iterator GetAlternateProtocolIterator(
        const url::SchemeHostPort& server);

    // Return the canonical host for |server|, or end if none exists.
    CanonicalHostMap::const_iterator GetCanonicalHost(
        const url::SchemeHostPort& server) const;

    // Remove the cononical host for |server|.
    void RemoveCanonicalHost(const url::SchemeHostPort& server);
    void ExpireBrokenAlternateProtocolMappings();
    void ScheduleBrokenAlternateProtocolMappingsExpiration();

    SpdyServersMap spdy_servers_map_;
    Http11ServerHostPortSet http11_servers_;

    AlternativeServiceMap alternative_service_map_;
    BrokenAlternativeServices broken_alternative_services_;
    // Class invariant:  Every alternative service in broken_alternative_services_
    // must also be in recently_broken_alternative_services_.
    RecentlyBrokenAlternativeServices recently_broken_alternative_services_;

    IPAddress last_quic_address_;
    SpdySettingsMap spdy_settings_map_;
    ServerNetworkStatsMap server_network_stats_map_;
    // Contains a map of servers which could share the same alternate protocol.
    // Map from a Canonical scheme/host/port (host is some postfix of host names)
    // to an actual origin, which has a plausible alternate protocol mapping.
    CanonicalHostMap canonical_host_to_origin_map_;
    // Contains list of suffixes (for exmaple ".c.youtube.com",
    // ".googlevideo.com", ".googleusercontent.com") of canonical hostnames.
    CanonicalSufficList canonical_suffixes_;

    QuicServerInfoMap quic_server_info_map_;
    size_t max_server_configs_stored_in_properties_;

    base::WeakPtrFactory<HttpServerPropertiesImpl> weak_ptr_factory_;

    DISALLOW_COPY_AND_ASSIGN(HttpServerPropertiesImpl);
};

} // namespace net

#endif // NET_HTTP_HTTP_SERVER_PROPERTIES_IMPL_H_
